Ai ga Nakuchane

Yuzuru is an orphan student but does not feel lonely because of his wise, diligent and faithful dog, Souichirou. One day Yuzuru is greatly shocked by the news of his dog being hit by a car. The driver, whose name is also Souichirou, offers to pay the vet's fee and help instead of the dog. Yuzuru falls in love with Souichirou but finds it difficult to know about Shouichirou, which is secretive by nature. Turns out that Souichirou is the CEO of a construction company and has a serious conflict with his brother in law about a succession.
(from B-U)